<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<style type="text/css">
			*{
				padding: 0;
				margin: 0;
			}
			.div01{
				width: 200px;
				height: 200px;
				background-color: blue;
			}
			/*600-900  变成红色*/
            @media only screen and (min-width: 600px) and (max-width: 900px) {
            	.div01{
            		background-color: red;
            		/*display: none;*/
            	}
            }
             
			 /*1 2 3
			 
			 12
			 3
			 
			 1
			 2
			 3 */
			
		</style>
		
	</head>
	
	<body>
	          
	          <div class="div01">
	          	
	          </div>
		
	</body>
</html>
